Device for drawing parallel lines.



A. DANIELSSON.

DEVICE FOR DRAWING PARALLEL LINES.

APPLICATION HLED MAR. 25. 1916.

lifiwfi fl Patented Dec. 11,1917.

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AUGUST DANIELSSON, OF LONDON, ENGLAND.

' ioEvrcE Foal DRAWING rAnA LE LINES.

I Specification of Letters Patent.

Patented Dec. 11, 1917..

Application filed March 25, 1916. Serial No. 86,736.

To all whom it mag concern.-

Be itknown' that I, AUcUsrDANmLssoN,

asubject of the King of England, residing at London, England, have invented certain 1 eme sin vices or ra i ar- Imp ov nt De f D wngP -allel Lines, of which the following is a specification.

The present inventionrelates toa device for facilitating the drawing of-parallel lines and consists in the combination with two members, for instance those of-an ordinary parallel ruler, of two vertical finger-operated keys mounted on such members, one on each, and of means actingon the two members in such a fashion that an alternate ver tical pressure-on-the keys brings about the step-by-step movement of the ruling device.

The invention isillustrated by way of example in the accompanying drawings,

Figure 1 representing a partial plan of a parallel ruler fitted with'the device.

Fig. 2, a central section through one'of the keys viewed in the direction of the arrow, 0;,

Fig. 8, a similar section of the other key, and

Fig. 4, an elevation of one of the keys seen in the direction of the arrow 6.

Fig. 5 is a View of one of the details of the device.

Fig. 6 is a plan of a device of a modified construction, and

F ig, 7, a sectional side view of a key show ing a modified construction of the latter.

1 and 2 are the blades of an ordinary ruler and they are fitted with keys 3 and 4 which are slidably held in hollow uprights 5 secured to the blades 1 and 2. Two arms 6 and 7 are connected respectively to the blades 2 and 1, the free end of each arm being guided in a slit made for the same in the key support of the opposite blade. Wedges 8 and 9, formed respectively on the arms 6 and 7, are adapted to move in slits 10 made for the same in the uprights 5. The keys cooperate with the inclined surfaces of these wedges for forcing the latter out of the slits 10, and the arrangement is such that a depression of the key 3 pushes the arm 6 and the blade 2 backward, and a depression of the key 4 pulls the arm 7 and the blade 1 in the same direction. The keys are so arranged that they can be operated by two fingers of the same hand, and the step-by-step movement of the ruler can thus be easily effected by one hand, the keys being simply alternately depressed. The pressure on one key steadies the blade to which it iscon nected while the other blade is being moved.

A lug 11 on the free end of the arm 6 limits the movement of the rear blade 2 by abutment against the upright 5. The movement of the blade 1 is limited by a screw spindle which abuts against the other upright and which can be adjusted for varying the spacing of the steps. A forked piece 13 secured to the arm 7, holds the screw. spindle spindle and held in the fork of the piece'13 so that it can be readily turned with a finger,

being employed for varying thepositionbf the spindle. A plate 15, connected to the outer end of the spindle 12, moves over the arm, as shown in Fig. 5, and prevents the spindle from rotating about its axis: The plate, moreover,indicates on a scale 16 on the arm 7 thespacing of the steps.

It is evident that a spring, for instance 17 (Fig. 6), may be employed for moving one of the members, in which case the key of the other member simply consists of a rigid post 18 on which a finger is placed for holding this member in position while the spring acts. At the subsequent depression of the key 4 the other member is moved up and the spring tensioned or compressed.

The key or keys, instead of acting on an inclined surface may have the movement transmitted to the arm by other means, for instance such as indicated in Fig. 7. The key 19 is here formed with teeth which mesh with a wheel 20 held in the upright 21. The arm 22, which operates like the arms in the previous construction, has a rack which also meshes with the wheel 20 and transmits the motion to the opposite member of the ruling device.

I claim 1. A device for facilitating the ruling of parallel lines, comprising the combination with two parallel ruling members connected by parallel links, of two finger-operated keys mounted on such members one on each,

so that it can move freely in a longitudinal directioina milled nut 14, mountedon the and means acting on the two members in such a fashion that an alternate vertical pressure on the keys brings about the step-,

and two armsconnected to such members one to each, each arm cooperating wlth the key of the opposite member in such a fashion.

that an alternate vertical pressure on the keys brings about the step-by-step movement ofsaid members. I V

3-. A device for facilitating the ruling of parallel lines, comprising the combination with two parallel ruling members connected by parallel links, of two hollow uprights mounted on such members one on each, vertical keys mounted slidably in said uprights, and two arms connected to said members one to each, each arm cooperating with the key of the opposite member in such a fashion that an alternate vertical pressure on the keys brings about the step-by'step movement ofsaid members.

:4. A device for, facilitating the ruling of parallel lines, comprising the combination with two parallel ruling members connected by parallel links, of two slotted uprights mountedon such members one on each, vertical keys held slidably in said uprights, two

arms connected. to said members one to each, the free end of each arm being accommodated in a slot in. the upright of the opposite member, and Wedges formed on the free ends Copies of this patent may be obtained for of said arms so as to support and cooperate with said keys in such a fashion that an alternate vertical pressure on the keys brings about the step by-step movement of said members.

5. A device for facilitating the ruling of parallel lines, comprising the combination with two parallel ruling members connected by parallel links, of two uprights mounted in said members one on each, vertical keys slidably held in said uprights, two arms connected to said members one to each, each arm cooperating with the key of the opposite member 1n such a fashlon that an alternate vertical pressure on the, keys brings about the step-by-step movement of said members, a lug formedon one arm so as to limit the separation movement of the members by abutment against the upright of the key by which it is actuated, and an adjustable screw on the other arm arranged so as to limit the closing-up movement of the members by abutment against the opposite upright.

AUGUST DANIELSSON. \Vitnesses J OHN HANS, SYDNEY R TAYLOR.

five cents each, by addressing the, "Commissioner or Iatents, Washington, D. 0. 

